Pump or motor



E. K. BENEDEK PUMP 0R MOTOR June 12, 1951 7 Shets-Sheet 1 Filed Nov. 14,1944 June 12, 1951 E. K. BENEDEK PUMP 0R MOTOR Filed Nov; 14, 1944 7Sheets-Sheet 2 MUH m INVENTOK flf/f/(EENEDEK 6% w ld ATTO [ENEYS June12, 1951 E. K. BENEDEK 71 PUMP R MOTOR Filed Nov. 14, 1944 I 'rSheets-Sheet s INVENTOZ fLE/rKBE/VED 4'4 ATTORNEYS June 12, 1951 BENEDEK2,556,717

PUMP 0R MOTOR Filed Nov. 14, 1944 7 Sheets-Sheet 4 INVEN TOR: E L 5k h..Zf/VEBEA y KJM Ywfi 9 ATTOENEYS June 12, 1951 E. K. BENEDEK ,71

PUMP 0R MOTOR.

Filed Nov. 14, 1944 7 Sheets-Sheet 5 S v. w M 0 T T INVENTOFZ :2 [K KBEN EDEK E. K. BENEDEK PUMP 0R MOTOR June 12; 1951 7 Sheets-She et 6Filed Nov. 14, 1944 NNK skim! ih s E. K. BENEDEK June 12, 1951 PUMP 0RMOTOR '7 Sheets-Sheet 7 Filed Nov. 14, 1944 Z/ek 1a. Berzedk ,Mmhw WM?diio megs Patented June 12,, 1951 UNITED STATES PATENT QFFICE run? RMoron Elek KsBeiiedek, Chicago, Ill.

Application- Nevember 14, 1944, Serial No. 563,353

This invention relates to pumps or motors and more particularly tohydraulic pumps or motors of the kind including a cylinder barrelrotatable about a fixed intleand in which pistons reciprocable incircumferentially spaced radial cylinders on the barrel are operated bytlirust=transmitting means engageable with a reactance member orassembly eccentric to the pintle axis. I

An object of the invention is to provide s'truo turalimbrovements ina-pump or motor of the class referred to by which the machine is madecapable of" operating with increased reliability and 'efilciency and atvery high working pressures,

Another objectof the invention is to provide a pump or motor havingthese desirable char= acteristics' and which is of light, compact eon=structi'on rendering it especially suitable for ex acting gruellingservice, such as for operating aircraft-controls. v

Another object of the invention is to provide such a-bu'm or motorapar'atus which is con structed to enable the high speed working parts tobe lubricated more efficiently than heretofore,- so as to make very highoperating speeds safe, thereby enabling a-srnall compact unit'to carrylarg oads;

Another obje'ct'of'the" invention is to provide an improved preloadedbearing mounting for rotating parts of such machines.

Another object of the invention is to provide an im roved drive couplingarrangement for a pump or motor or the kind referred to.

A-ful'ther object-0f the invention isto provide unimproved reactanceassembly. Other objects will becomeap arent from areadirlg of the fol=lowing detailed-description; the appended claims, and the accompanyingdrawings, in which:

Fig-lire 1 is a longitudinal-section of a hyd' iilic' pump or motorembodying'the' invention, the section being taken on the-line l--| ofFigure '3 Figure 2 is a longitudinal section of the-pump or motor shownin Figure 1,- the section being taken on the liner-2 of Figure 3, withrotary parts shown as being'angula'rly displaced from thepositions-shown in Figure 3;

Figure 3 is a transverse seotion on the line 3- 3 of Figure 1-;

Figure 4 is an end elevation looking in the direction of the arrow 4inFiglire 1;

Figure 5 is a detail longitudinal seotior'lal View of acheck valve drawnon an enlarged scale; Figureu6- is a fragmentary detail section of partor a reactance rotor showing particularly 2 the relation of a pair ofadjacent thrust blocks to a clamping bolt;

Figure 7 is a fragmentary longitudinal section of a modified arrangementfor journaling' a rotatable cylinder barrel;

Figure 8 is an enlarged copy of Fig. 1 showing only the preloadedbearing mounting of the pintle and barrel, and the preloaded bearing ofthe impeller shaft; I

Figure 9 is a section through line 81-9 of the larger pintle bearings ofFig. 8, showing the deformation of the rolling element slightlyexaggerated to illustrate the preload on the rolling elements in thedirection oftheir' rotation;

Figure 10 is a transverse section taken alon line iii-10 of Fig. 8showing the deformation of the preloaded antifrictiorl elements"slightly exaggerated for elear'ness of illustration;

Figure 11 shows a fragmentary portion of one of the bearings shown inFig; 9 with the cage removed, and with the staggered, double rowstraight roller elements, and

Figure 12 shows a fraction of the staggered cage elellle'lit Of thebearings shown in Fig. 11.

structure's embodying the invention may be adaptedtooperate either asumans or motors. In the following" detailed descri tion of representative embodiments of the inventiyestrucone reference will be made toits functioning when operating as a pump, but it will be understood thatlike other structures of the same general class it may operatereversely, that is as a hydraulic motor when sup lied with worki'ngfiuld under pressure.

Throughout the s ecifications of this invention, the word or termpreloaded bear'i'ngor bearings is" intended to comprehend suchantifriction ball or roller bearing structure inwhi'ch in assembly theraces, which are the relatively r0- tating bearing members, as well asthe balls or rollers which are the load transmitting rolling elements,are under positive preload. This preload is obtained in assembly bydesigning the relatively rotating races in such relation with respect tothe inner and outer bearing housing members, that by press-fitting theraces in their res ective housing the space defined therebetween for"the anti-friction rolling elements will be less radially than the radialdimensions of the ro ling elements. By this simple provision andwithoutanyextra member or costs the whole bearing and in it, its rollingelements will be positively preloaded and all radial lo'oseness ironith'ebearing itself, eliminated.

The embodiment shown in l' igures'l to '6 in- 3 clusive comprises a pumpcasing generally designated A and including a cylindrical body portion iand a manifold cover plate 2 mounted at the open end of the body I andclamped and held in assembled relation to the body I by bolts 2 or othersuitable means. The end cover 2 supports a fixed pintle B which extendsinto the casing and is surrounded by a rotatable cylinder barrel memberC provided with a plurality of circumferentially spaced radial cylinders3. Cylinder ports. t communicating with the 0571-. inders 3 are adaptedto cooperate in a known manner with pintle discharge ports 5 and intakeports 6. municate with a discharge passage 3 extending longitudinallywithin the pintle to a-radial discharge passage 8 in constantcommunication larly an antifriction bearing assembly 22 comprisingrolling elements 22*; an inner race 22 and a spacer ring or cage 22 isinterposed between the barrel bore and the outer end portion of thepintle. The races 21 and 22* are recessed to provide depressed annulartrackways for the rollers 2N and 22 No separate outer races are providedin the embodiment shown, but it shall be understood that I do not limitmy invention toythis embodiment" alone, but may use any standardmodification of these external two row straight roller bearings, such asa complete bearing having both inner and outer races or a The pintledischarge ports 5 com so-called inverted form wherein the rollers arecarried by an outside race and bear directly and without an'inner raceon the pintle. As shown best in Fig. 8, the rollers Zl and 22 insteadwith a chamber 9 in the manifold plate 2, thechamber 9 being adapted tocommunicate withexterior piping fitted to a connection It. Similarly,the pintle intake ports 6 communicate with intake passages ii extendinglongitudinally through the pintle and being connected toradial passagesl2 which communicate with a manifold intake chamber [3 adapted tocommunicate with outside piping through a connection M.

Pistons l5 'mounted for reciprocation in the Qylinders 3 respectivelyare formed or equipped with tangential cross heads orthrust-transmitting connections IE adapted to have rotary drive andthrust-transmitting connection with a reactance ring member or assemblyD, the construction of which will be explained later. For the present itis sufficient to state that the reactance ring assembly D is mounted forrotation about an axis eccentric to the common axis of the pintle andcylinder barrel.

In operation, the cylinder barrel C is rotated about the pintle Bwhereby the pistons i5 and the cross heads l6 impart rotary drive to thereactance ring assembly D and, due to the eccentricity of the assemblyD, the pistons are reciprocated. The registration of the cylinder ports4 with the pintle ports 5 and 6 is so timed with respect to thein-and-out travel of the pistons that fluid is drawn into the cylindersduring outward strokes engage the bores 19 and 20 directly and the boresI9 and;20, which thus serve as raceways, are smoothly finished andhardened so as to have all of the properties required for a bearingrace.

Anti-friction straight roller bearing assemblies 2i and 22,respectively, when preloaded by radial compression forces of theassociated pintle B and barrel flange C, respectively, will be deformedas in Fig. 9 to the extent of the maximum rated pump load in such amanner that irrespective of the instantaneous load or operating pressureof the pump, all rolling anti-friction elements will be loaded to theextentof the maximum rated load of the pump, thus as shown inFig. 8,they will be compressed radially and assume slightly deformed egg orelliptical form in the direction of their rotation. Due to thisprecompression of the rollers and associated race members of bearings 2iand 22, the operating clearance between pintle and barrel not only canbe kept down to a practical minimum and up to the maximum operatingpressure of the pump, but this operat ing clearance can be stabilizedand maintained during the useful life of said preloaded roller of thepistons and is forced from the cylinders bearings which hold the barrelso accurately aligned with respect to the pintle as to permit operationunder very high working pressures without undue slip fluid loss and withminimum wearing of the parts under heavy load operating conditions. and8 to 12 the cylinder barrel C is formed with a central bore portion I 1in the region of the cylinders 3. The bore I! fits closely over thecentral or adjacent pintle surface [8 with small operating clearanceinsufiicient to permit substantial slippage of fluid under pressures ashigh as 3000 pounds per square inch. On opposite sides of the barrelbore [1 are barrel end bore portions l9 and 28 of somewhat largerdiameter than the bore ll so as to be spaced radially from the pintleportions which they respectively surround. An antifriction bearingassembly 2! including rolling elements 2 l an inner race 21 and a spacerring or cage 2| is interposed in the annular space between the barrelbore l9 and the pintle B. Simi- In the form shown in Figures 1 to 6 1bearings 2| and 22. Such greatly reduced and evenly distributed runningclearance between pintle and barrel will result in reduced slip andreduced mechanical friction.

The bearings 21 and 22 are preloaded radially in order to obtain morestability of the'operating clearance between thepintle midsection J3 andthe barrel bore ll. The preloading is imposed on the bearings by forcingthe sets of rollers and their respectively associated inner races on thepintle to provide a press fit of the races on the pintle. The races aremachined to inside diameters slightly smaller than the normal diametersof the cooperating pintle portions so that when the races are pressedupon the pintle the races are expanded or forced radially outwardly,thus forcing the associated rollers 2 l and 22 radially outwardlyagainst the barrel bores J9 and 29. On the other hand, barrel bores l9and 20 are so machined that their respective inside diameters will beless than the expanded outside diameters of bearings 2i and 22, with apredetermined amount. The rollers 2 l and 22 thus are assem bled underradial compression from the inside as well as from the outside therebyproviding the desired preload condition.

Inasmuch as the inner bearing race 21 is press fitted on the pintle, itis not necessary to hold it in fixed axial position, but if there shouldbe any tendency forit to shift longitudinally of the pintle, itsshifting movement would be limited by a-shoulder 23'on the cylinderbarrel and a shoulder Men the end cover 2. The race. 22 is held;

coaxial with the pintle B. The preloaded bearing 21 includes an innerrace member 21 the left side face of which abuts and has fluid tightengagement with a radial. shoulder 32 on the part 28. The race 21! isgrooved to receive ball rollers ll which also are received by a groovedouter race 21 mounted in a counter bore 33 formed in the casing body I.In opposed relation to and axially spaced from the radial shoulder 32 isanother shoulder 34 which abuts the right hand outer face of the bearingrace 21.

After bearing 21 is preloaded, either in the assembly or in the processof manufacture as shown in Fig. 10, under the balanced compressingforces of the races and their respective housing, the originally andgeometrically pure spheres now become compressed to egg-shaped orellipsoidal rolling elements (see Fig. and instead of having pointcontact with their respective race walls, they will have a contactinvolving an elliptical area of substantial magnitude. Due to thispreload to the approximate amount of the maximum rated load of the pump,during maximum load operation of the drive shaft 30,'there will be noadditional deformation in the balls 21 of the preloaded ball bearing 21,consequently the drive shaft 3%! will operate with a minimum relativeeccentricity with regard to the axis of pintle and the barrelrespectively. With such close eccentricity the cylinder barrel with itsend flanges I9 and 2t, and supporting preloading roller bearing 2! and22 will operate with a minimum wabbling effect, thus the preload ofbearings 2i and 22, and the preload of bearing 21 are closelyinterdependent, and the success of the one depends greatly on thesuccess of the other. The illustration of Fig.-

10 is slightly exaggerated, but actual preload in this specification isdefined as one which produces positive precompression of the rollingelements of a preloaded bearing. Since the rolling of the ballsisconfined to a channel shaped race, the compression of the balls ismost striking in the direction of the rotation of the bearing.

A preloaded pintle nose thrust bearing 35 is received in an opening 3'6in the end of the pintle and abuts a shoulder 31. A plug 38 press fittedinto the inner end of the sleeve extension 36 also abuts or bearsagainst the nose bearing 35.

When the parts are assembled and the cover 2 and body I are drawntogether axially, the shoulder' 34 presses the race 21 toward the left,causing the balls 21 and the inner race 21 also to be forced toward theleft. Thus the inner race 21 is pressed against the radial shoulder 32,forcing the cylinder barrel toward the left and causing the plug 38 topress the nose bearing 35 against the pintle shoulder 31. In this waythe bearings 27 and 35 are preloaded and anchor the right hand end ofthe cylinder barrel against axial movement.

A further feature of the invention resides in the provision of means forflooding the interior of the casing A and the operating parts containedtherein with fluid lubricant independent of the working fluid flowing toand from the cylinders. Asindicatedim Figure l a.reservoir.39 locatedexteriorlyl ofthe pump communicates constantly with the interior of thecasing A- by a pipe or conduit 40. The reservoir 39 constitutes anexterior source of fluid pressure which, in the illustrated apparatus,is a static pressure due to location of the reservoir at a higher levelthan the pump. It will be understood that the lubricating fluid may bemaintained under pressure by other suitable means. When it is desired toremove the fluid from the casing, it may be drained through an opening4| which normally is closed by a plug (not shown) In order to preventthe escape of fluid through the space between the sleeve 36 and thecasing opening 3|, the casing body I is formed with a seal chamber 42 inwhich is mounted an expansive sealing or packing device including a cage43 and an annular sealing element 44 pressed by springs 45 into slidingor rubbingv contact with the adjacent face of the bearing race 21 whichis smoothly finished and suitably hardened. The sealing element 44 maybe maintained centralized by a ring of packing or the like 48 which isdisposed between the cage t3 and the sealing element 44 and serves toprevent the escape of lubricating fluid from the rear of the sealingelement 44. Thus it will be observed, that a balanced mechanical seal isprovided, which is not only very compact, but is so constructed that aplurality of axial springs function only to press the seal nose againstthe polished bearing race at a constant pressure and the springs are notrequired to act against the hydrostatic pressure of the housing.

The rotary reactance assembly D previously referred to only generallycomprises two end plate members 41 and 48' spaced from each otheraxially of the pintle and formed respectively with opposed circularlygrooved seats 4e and 5B for receiving a plurality of thrust blocks 5ihavingtangential slide ways or working faces 52 adapted to accommodatethe piston cross heads Hi. In order that the individual thrust blocks 5|may each be aligned in exact tangential relation to its associatedpiston I5, the blocks are sized so as to leave a substantial clearancespace between contiguous end faces of adjacent blocks. This clearancepermits the blocks to be adjusted circumferentially without touchingeach other so that each block may be positioned in exact tangentialrelationship to the associated piston. After the blocks 5| have beenadjusted, the end members 47 and 48 are drawn towards each other and arethus clamped against the blocks 55 by means of bolts 53. Each bolt 53passes between contiguous end faces of two adjacent blocks 5| and inorder that the bolts will not interfere with the circumferentialadjustment of the blocks, the block ends are formed with cut-outs orrecesses 54 through which the bolts extend with substantial clearance.The recesses 54 are suifi'ciently large to insure that the blocks 5iwill always be free of engagement with the bolts 53.

The reactance assembly D is journaled in the casing A by antifrictionbearing assemblies 55 and 56 interposed between the casing body I andthe end members 48 and 41 respectively. The bearings 55 and 55, whichare held in place by snap rings 55 and 56 mount the reactance member Dfor rotation about an axis eccentric to the pintle axis. A shroud ringor band 57 surrounds the blocks 5| and engages the peripheral portionsof the end members 41 and 48.

The bearing 35 is not flooded directly with free lubricant from theexterior source 39'. ln order to assure constant and eifectivelubrication of the bearing 35, the pintle is formed with an annulargroove 58 which is always flooded with lubricant and from whichlubricant flows into a radial pin-- tle passage 59 and an axial pintlepassage 65 which discharges through a relief valve 6| into a lubricantchamber 62. The valve bi may be of conventional construction including avalve seat 62 and ball valve 63 urged against the seat by a spring 84.

In operation, fluid under pressure in the small clearance between thepintle surface It and the cylinder barrel bore ll works its way into thechamber 62, maintaining the latter flooded so that when the plug 38 isrotated, the body of lubricant in the chamber 62 will be whirled aroundand forced against the rollers or balls of the bearing to maintain thelatter in a body of lubricant under pressure created by centrifugalforce. Any

excess pressure built up in the chamber 62 is relieved by opening of thevalve 6 i. When the pump stops operating, the check valve 6! closes soas to maintain the supply of lubricant in the chamber 62 in readinessfor lubricating the bearing 35 centrifugally immediately upon startingor" the pump.

For coupling the pump to a driving motor or engine a flexible couplingmember comprising a reduced stem section 65 and splined ends 66 and 3'?is loosely held within the shaft part or sleeve extension 30, which issplined to receive one splined .1

end 66 of the coupling member. A snap ring 68 retains the couplingmember in place with its left hand end abutting a shoulder 69 providedby the adjacent end of the plug The other splined end 6'! of thecoupling member is adapted to be extended into a splined sleeve or thelike driven by the motor or engine.

By forming the sleeve 3!! of the separate member 28 hollow throughout,broaching to form the splines or teeth is facilitated. The splinedsleeve is then closed at its inner end by the presstted plug 38 whichprovides the abutment shoulder 69 for the coupling.

In the embodiment shown in Figure '7, the preloading of the cylinderbarrel journals is effected partially by press fitting bearings betweenthe cylinder barrel and the pintle and casing respectively and partiallyby adjustment of the ball bearing assemblies effected after the bearingshave been put in place. The illustrative embodiment of this form of theinvention includes a casing element E, pintle F, and cylinder barrel Gformed with cylinders "iii adapted to communicate by ports 11 withpintle ports 72 and 13. Reactance mechanism similar to that previouslydescribed or of other suitable form may be provided for reciprocatingpistons id in the cylinders 10.

The cylinder barrel element G is formed with end bores 15 and it whichare spaced radially from the pintle element F to provide for theinsertion of antifriction bearings H and 13 in the bore l6 andantifriction bearings 79 and 8G in the bore 15. The bearing assembly 11comprises an inner race Ti grooved to receive rollers 71* which rollalso on an outer race Ti The assembly 11 is press fitted between thebarrel bore 16 and the pintle so as to place the rollers 11 and theassociated races under radial compression. The bearing i9 is similar tothe bearing 11 and includes an inner race lii grooved to receive rollers19" which operate within an outer race 18. The bearing assembly '39 ispress fitted between the pintle and the barrel bore 75.

The bearing assembly 78 is of the ball type and it is preloaded by pressfitting both of its races 18 and 18 with a positive interference fitbetween the pintle F and barrel flange G. This can be achieved by makingthe outside diameter of the pintle greater than the bore of the race 18and the inside diameter of flange G smaller than the outside diameter ofrace 18. This bearing i adapted to be preloaded by forcing one of itsraces axially with respect to its other race. It is shown as includingan inner race 18*, a set of balls 18 and an outer race 18. Similarly thebearing assembly includes an inner race 86 balls 80 and an outer race80.

Press fitting of the bearings 11 and 19 between the pintle and theassociated barrel bores 16 and '55 respectively tends slightly toincrease the diameter of the barrel bore walls. In order that thebearings l8 and 80 may be additionally and equally preloaded tocompensate for the expansion of the barrel bores a nut 8| threaded onthe free end of the pintle F is drawn against a washer 82 to press onthe inner race 86 of the bearing assembly 86. This axial pressure istransmitted through the complete bearing assembly 80, the outer bearingrace 79, the barrel G, the outer bearing race 17 and the completebearing assembly E8, the inner race 18 of which abuts shoulder 83 of thepintle. Although this does not tend to load the bearing assemblies 71and i9 additionally, the axial pressure imposed on the assemblies '13and $0 does produce in them a radial preload which can be made to equalor to bear a predetermined relation to the press-fit preloading of thebearings 11 and 19.

A shaft extension 84 has a flange 85 connected to the barrel G by screws86. The extension 84 projects through a bore Bl in the casing E and isjournaled in the casing by antifriction bearing assemblies 88 and 89interposed between the pintle and the casing bore 87. The bearingassembly 88 is similar to the assemblies 11 and 19 previously describedand is preloaded by being press fitted between the pintle and thecasing. The bearing assembly 89 is similar to the bearings i3 and 8H andis preloaded also by being press fitted between the drive shaft 84 andhousing flange bore 3'? with positive interference fit with itsrespective races 89 and 89 between the shaft 8 and the flange bore 81respectively. This can be achieved by making the outside diameter ofshaft 84 greater than the inside bore of inner race 8%, and by makingflange bore 81 less than the outside diameter of race 39; The preload ofthis bearing can be adjusted, and additionally increased by turning anut 90 threaded on the shaft extension 84 to draw it up against a washer9i so as to press the bearing assembly 89 to the left, which in turnpresses the outer race of the bearing 88 against a casing shoulder 92. Acap 93 secured to the casing E by screws 94 is equipped with shaftpacking 95.

The axially spaced and aligned three groups of preloaded combinationbearing assemblies cooperate in a unique manner. The mounting of c theroller and ball bearings in the barrel flanges cfier specificadvantages, irrespective of the order in which the roller and ballbearings are combined. If the roller bearings are mounted first and theball next to it, the excess enlargement of the flange bore due to thepreload of the roller bearing can be taken up readily by the additionalpreload or adjustment of the ball bearing, thus both kind of bearings,the ball and the roller, can be preloaded substantially to the sameamount of their respective capacities. The roller bearing will be theprincipal agent of radial load, whilethe ball bearing though it willhelp in radial load,.will be the principal agent of axial positioningand thrust If on the other hand, the order of the mounting is reversed,during preloading, in the same barrel bore, the ball bearing will beless preloaded than the following roller bearing, and automatically theproportion of preload will be in the ratio of the respective capacitiesof the two different types of bearings, which is a great perfection inthebearing combination and an advantage at the same time.

The same is true for bearings 88 and 89. Depending on the assignment ofthe pump, either the roller or the ball bearing will be assembled first.If the thrust force is toward the left, the present order is the properone. If the dominating thrust force points to the right, the ballbearing'should come first, and contact with its thrust shoulder thefixed outer race of the roller hearing. The mounting can be obtained bythe complete reversal of the two bearings as one unit.

The apparatus disclosed by way of example embodies the invention in thepreferred form, but it will be apparent that changes may be made in theparticular construction and relative arrangement of the illustratedparts without departing from the invention as defined in the claims.

I claim:

1. In a pump or motor, a casing; a cylinder barrel provided with aplurality of circumferentially spaced radial cylinders; means mountingsaid cylinder barrel for rotation including an antifriction bearinginterposed between said casing and an end part of said cylinder barreland including an inner race member and associated rolling elements, saidend part supporting said inner race and having a radial shoulder againstwhich the inner face of said race abuts; means supplying lubricatingfluid under pressure to the interior of said casing to flood saidbearing; a seal chamber in said casing adjacent the outer face of saidrace; and a balanced mechanical seal in said chamber including anannular element pressing axially into sealing engagement with said raceouter face and also including packing means preventing leakage betweensaid annual element and said casing.

2. In a pump or motor, a casing; a cylinder barrel provided with aplurality of circumferentially spaced radial cylinders; means mountingsaid cylinder barrel for rotation including an antifriction bearinginterposed between said casing and an end part of said cylinder barreland including an inner race member and associated rolling elements, saidrace member being mounted in fluid tight engagement with said end part;means supplying lubricating fluid under pressure to the interior of saidcasing to flood said bearing; a seal chamber in said casing adjacent theouter face of said race; and a balanced mechanical seal in said chamberincluding an annular element pressing axially into sealing engagementwith said race outer face and also including packing means preventingleakage between said annual element and said casing. v

3. In a pump or motor, a casing; a pintle mounted in said casing; acylinder barrel journalled for rotation on said pintle and beingprovided with a plurality of circumferentially spaced radial cylinders;an opening in one end of said casing opposite the adjacent end of saidcylinder barrel; a shaft part fixed with respect to and extending fromsaid end of said cylinder barrel 10 and into said opening and having aradial shoulder'adjacent said barrel end; a counter bore in said casingsurrounding said shaft part and terminating in an opposed shoulderfacing towards said barrel end and being spaced outwardly from saidradial shoulder; an antifriction bearing comprising rolling elements andinner and outer races, the-inner race fitting over said shaft part andabutting said radial shoulder, and the outer race fitting in saidcounter bore and abut-ting said opposed shoulder; a seal chamber in saidcasing outwardly beyond said antifriction bearing; and

a balanced mechanical seal in said chamber'ineluding an annular elementpressing axially into sealing engagement with the outer face of-saidinner race;

4. In a pump-or motor, a casing; a pintle mounted in the casing; acylinder. barrel rotatable about said pintle and having a boresurrounding said pintlewith working clearance between the pintle and thebore wall; portsiin said pintle; cooperating ports in said cylinderbarrel; a closed chamber between said cylinder barrel and one endportion of said pintle; bearings in said chamber and operativelyinterposed between said pintle and said cylinder barrel; a lubricantpassage extending through a part of said pintle and communicating at itsopposite ends respectively with said chamber and with a source oflubricant; a relief Valve in said passage-way for retaining fluidlubricant in said chamber but being operable by excess fluid pressure insaid chamber for permitting lubricant to flow from said chamber intosaid passage-way.

5.'In a pump or motor, a casing; a pintle mounted in the casing; acylinderv barrel rotatable about said pintle and having a boresurrounding said pintle with working clearance between the pintle andthe bore wall; ports in said pintle; cooperating ports in said cylinderbarrel; a closed chamber between said cylinder barrel and one endportion of said pintle; bearings in said chamber and operativelyinterposed between said pintle and said cylinder barrel; a lubricantpassage extending through a part of said pintle and communicating at itsopposite ends respectively with said chamber and with the interior ofsaid casing; means for connecting the interior of said casing to asource of fluid lubricant under pressure; a relief valve in saidpassage-way for retaining fluid lubricant in said chamber but beingoperable by fluid pressure in said chamber for permitting lubricant toflow from said chamber into said passage-way to thereby control thepressure of said closed chamber and of said working clearance betweensaid pintle and said bore wall of said barrel.

6. In a pump or motor, a casing; a pintle mounted in said casing; acylinder barrel r0- tatable about said pintle and being provided with aplurality of circumferentially spaced radial cylinders; a separatemember attached to said barrel at one end thereof and being formed witha sleeve extending axially from said cylinder barrel, the outer end ofsaid sleeve being internally splined to receive a splined coupling; aplu fltted tightly in the inner end of said sleeve and providing anabutment for the inner end of the coupling; pistons respectivelyreciprocable in said cylinders; reactance and thrust means forreciprocating said pistons in response to rotation of said barrel andcylinders; and means for valving flow of fluid to and from saidcylinders.

'7. In a pump or motor, a casing, a pintle mounted in said casing; a clinder barrel ro- 11 tatable about said pintle and being provided with aplurality of circumferentially spaced radial cylinders; a separatemember attached to said barrel at one end thereof and being formed witha sleeve extending axially from said cylinder barrel, the outer end ofsaid sleeve being internally splined to receive a splined coupling; aplug fitted tightly in the inner end of said sleeve and providing anabutment for the inner end of said sleeve; an antifriction thrustbearing interposed between said plu and the adjacent end of said pintle;pistons respectively reciprocable in said cylinders; reactance andthrust means for reciprocating said pistons in response to rotation ofsaid barrel and cylinders; and means for valving flow of fluid to andfrom said cylinders.

ELEK K. BENEDEK.

REFERENCES CITED UNITED STATES PATENTS Name Date Benedek June 24, 1934Number Number Number 12 Name Date Smith Mar. 26, 1935 Ernst May 19, 1936Benedek Dec. 7, 1937 Benedek Sept. 13, 1938 DeBoysson Feb. 14, 1939Benedek Feb. 14, 1939 Benedek July 23, 1940 Ernst July 23, 1940 BenedekSept. 16, 1941 Benedek Mar. 17, 1942 Tucker Aug. 4, 1942 Benedek Apr.10, 1945 Grosser Aug. 7, 1945 Buckner Apr. 13, 1948 FOREIGN PATENTSCountry Date Great Britain June 26, 1935 France Jan. 16, 1933 OTHERREFERENCES Machine Tool Applications Publication, issued byNorma-Hofiman Bearing Corporation. Received April 20, 1937; page 5.

